The present invention relates to a drain connector and in particular, but not exclusively, to a drain connector for removable sinks or other appliances.
The inventor""s earlier patent applications GB 2243422 and EP 0916773, the contents of which are incorporated by reference herein, relate to plumbing fittings for connecting removable sinks and other appliances such as dishwashers and clothes washing machines to a mains water supply. The fittings allow the appliance to be rapidly disconnected and reconnected to the water supply without having to turn off the supply. This allows the appliance to be removed from its normal position for thorough cleaning both of the appliance and of the wall and floor around the position where it is normally located. This is very helpful where hygiene is of great importance, for example in hospitals and in restaurant kitchens.
In the prior art arrangements described above, the drain connector normally comprises a wall unit that is permanently connected to the sewers and a sink unit that is attached to the sink. The sink unit includes a spigot that extends horizontally from the rear of the unit and engages, in use, a socket in the wall unit through an O-ring seal. When the sink is removed the spigot is simply pulled out of the socket, and when the sink is returned to its normal position the spigot is simply reinserted into the socket to re-establish the drain connection.
While this arrangement operates perfectly satisfactorily, it does not meet certain American National Standards, which require drain connections to be xe2x80x9crodent proofxe2x80x9d. This is normally achieved in fixed sinks by providing a strainer that is fitted to the drain boss in the sink bowl. However, with drain connectors of the type described above, the mouth of the drain socket in the wall unit is left open when the sink is removed from its normal position. This creates a possible entry passage for rodents.
It is an object of the present invention to provide a drain connector that mitigates the aforesaid problem.
According to the present invention there is provided a drain connector including a fixed unit having a first drain conduit for permanent attachment to a drain pipe and a detachable unit having a second drain conduit for attachment to a removable appliance, the fixed unit including a first drain connector element and the detachable unit including a second drain connector element for detachable connection with the first drain connector element, the fixed unit further including a closure member that is adjustable between an opened condition and a closed condition in which it substantially closes the first drain conduit, to prevent the passage of rodents through the conduit.
When the closure member is in the opened condition, it leaves the drain conduit open, allowing the substantially unimpeded flow of liquid through the first drain conduit. When it is in the closed condition it substantially closes the first drain conduit to prevent the passage of rodents through the conduit. This makes the drain connector rodent-proof, allowing it to meet the requirements of American National Standards.
Advantageously, the closure member is biased towards the closed condition, ensuring that it closes whenever it is not held open.
The closure member is preferably constructed and arranged such that it adopts the opened condition when the first and second drain connector elements are connected. This allows automatic operation, the closure member opening when the first and second drain connector elements are connected and closing when they are disconnected.
Advantageously, the second drain connector element includes a spigot pipe element and the first drain connector element includes a socket for receiving the spigot pipe element, the closure member being engaged by the spigot pipe element when the first and second drain connector elements are connected. The spigot pipe element thus controls opening and closing of the closure member as the first and second drain connector elements are connected and disconnected.
The closure member may include at least one pivotable door. Preferably, the closure member includes a plurality of pivotable doors, arranged with their pivot axes around the periphery of an opening for receiving the second connector element.
The drain connector may include a guide structure for guiding the first and second drain connector elements into engagement. Preferably, the guide structure includes a plurality of convergent wall elements. This makes it easier to connect and disconnect the first and second drain connector elements.
The drain connector may include a seal element for sealing the connection between the first and second drain connector elements. The seal element may include an o-ring seal.
Advantageously, the first and second drain connector elements are constructed and arranged such that, in use, they are connected and disconnected by substantially horizontal relative movement, for example by pulling a wheeled appliance away from a wall.
According to a further aspect of the invention there is provided a detachable appliance including a drain connector as defined in any one of the preceding statements of invention, in which the appliance comprising a sink unit.
Advantageously, the sink unit is mounted on castors or wheels for ease of movement.
The sink unit may include a mains water connection apparatus for detachably connecting the sink to a water supply.